2 credits is correct.
That would have been converted to 15 points.
Until Jan 1, 2003 it was 1 credit per cruise no matter the stateroom category or length of cruise.
After Jan 1, 2003, an extra credit was given for cruises of 12 days or longer.
After Jan 1, 2004, an extra credit was given for cruises in a JS or better.
Conversion 21.01.11
Conversion from old cruise credits to cruise points:
If credits were 1-4, points = credits * 7 + 1
If credits were 5-7, points = credits * 7 + 3
If credits were > 7, points = credits * 7 + 13